Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Statement of Comprehensive Income [Abstract]
Net loss	$ (51,181)	$ (44,731)	$ (44,675)
Other comprehensive loss:
Unrealized (loss) gain on available-for-sale securities	(1)	(10)	34
Comprehensive loss	$ (51,182)	$ (44,741)	$ (44,641)

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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+ Details